Update - (Oracle Query)

The UPDATE statement in Oracle SQL is used to modify existing records in a table. It allows you to change the values of one or more columns for a specific set of rows.

Syntax

The basic syntax for updating data in Oracle SQL is as follows:

UPDATE table_name
SET column1 = value1, column2 = value2, ...
WHERE condition;

Here, table_name is the name of the table you want to update, column1, column2, etc. are the names of the columns you want to modify, and value1, value2, etc. are the new values you want to set. The WHERE clause is used to specify which rows to update.

Example

For example, suppose we have a table called employees with columns employee_id, first_name, last_name, email, and salary. We want to increase the salary of all employees with a salary less than $50,000 by 10%.

UPDATE employees
SET salary = salary * 1.1
WHERE salary < 50000;

Output

The output of the update statement will be the number of rows affected by the update.

Explanation

In the above example, we have used the UPDATE statement to modify the salary column for all rows in the employees table where the salary is less than $50,000. We have set the new value of the salary column to be the original value multiplied by 1.1, effectively increasing the salary by 10%.

Use

The UPDATE statement is used whenever we need to modify existing records in a table. This can be useful when we need to correct errors or update old data with new information.

Important Points

• The UPDATE statement is used to modify existing records in a table.
• The SET keyword is used to specify which columns to modify and what values to set them to.
• The WHERE keyword is used to specify which rows to update.

Summary

In summary, the UPDATE statement in Oracle SQL is used to modify existing records in a table. It allows you to change the values of one or more columns for a specific set of rows. By using the WHERE clause, you can limit the scope of the update to only certain rows in the table. The UPDATE statement is a powerful tool for correcting errors or updating old data with new information.